From Drought to Deluge: Planning a Garden to Withstand Weather Extremes
Over the past month, we have experienced two major weather patterns: hot and dry for several weeks with no respite in many locations, followed by extreme rainfall of 10”+ in a period of two or three days. While recent storms were particularly severe in certain areas, these weather patterns are not uncommon. We cannot control weather, but we can plan wisely and take some foundational steps to promote successful gardens through the extremes.
First and foremost, select a good site. Identify where wet and dry areas are. Dry areas may reveal themselves during periods of drought with grass turning more brown than other locations. Dry areas may exist because of soil type, soil compaction, or a shallow rooting zone from underground infrastructure. Avoid putting crops with high water demands or deep rooting patterns in these areas. Wet areas may exist because of a high water table, stormwater runoff patterns, a soil type that holds water excessively, being in a flood zone, or soil compaction. Consult the county GIS website to identify flood zones on your property. Avoid the flood way, and if possible, flood zones, when selecting your site. Consider establishing plants that don’t mind “wet feet” in those areas, such a silky dogwood or willow. Some poor drainage issues can be corrected. For example, you may be able to divert stormwater by fixing a malfunctioning culvert or ensuring that drainage areas remain free from debris. Do not place gardens over septic fields or drain sites. Areas regularly saturated with stormwater may be good candidates for rain gardens. More information.
Constructing and planting in raised beds can offer some protection to plants during times of high water or heavy rains. Raised beds can be made in native soil, by raking or shoveling soil in strips to form elevated areas to be planted, and lower areas as walkways. Bringing in compost or other garden soil can help elevate the beds without as much digging. Or, if you have the resources to do so, construct raised beds with wood or other materials and fill with a high quality raised bed soil mix. One advantage to raised beds, either with or without a frame, is that you typically do not need to spend as much time or fuel tilling to prepare the beds. Framed raised beds filled with a special mix tend to dry out more quickly, but this can be reduced by using mulches. Tips on constructing raised beds.
Soil compaction can be alleviated by deep tillage, if safe to perform, double digging, or application of gypsum may be warranted if the compaction is caused by sodium levels- a soil test can help you understand more. Another way to improve your garden’s resilience through both drought and excess rain is to build soil organic matter. Soil organic matter is the component of your soil that is living, decomposing, or in a stable decomposed form called “humus”. Commonly added sources of organic matter might be compost, animal manures, grass clippings, straw, and organic fertilizers. Other ways to add organic matter are to incorporate non-diseased plant residues into the garden after harvest is over, and prioritize planting cover crops in your garden when you have a window. Examples of fall-planted cover crops include oats, wheat, crimson clover, and Austrian winter pea. Cereal rye is common but difficult to manage with small tillers. Easy to manage summer cover crops include cowpea or southern pea, buckwheat, soybean, and German or Japanese millet. If you have a tractor with mowing capabilities you may be able to plant some of the taller or faster-growing summer covers such as sorghum-sudangrass, pearl millet, or sunnhemp.
One approach to resilience in the garden is through the lens of Permaculture. The term Permaculture stems from the words “permanent” and “agriculture”. Permaculture is a solution-oriented approach to modeling agricultural systems after nature in order to reduce inputs, make efficient use of resources, and promote resilience. Elements of permaculture systems are multi-functional and incorporate natural movement of elements such as water in a functional capacity. For an introduction to the Permaculture, see Appendix G from the Extension Master Gardener℠ Handbook.
Once you have selected your site, plan for droughts by considering your water sources. Install a rain barrel or water catchment system to capture water from roofs for use as irrigation water. Most vegetable gardens need about 1” rain per week to be most productive. It takes 623 gallons of water to provide the equivalent of 1” rain to 1000 square feet of garden space – you can also capture this amount with a 1” rainfall event from a 1000 square foot rooftop. You can feed water to the garden through simple drip irrigation systems, soaker hoses, or by filling watering cans. Water catchment systems can also reduce stormwater runoff. It is better to water deeply once or twice per week rather light waterings several times per week. Using straw or landscape fabric mulches allow water penetration, and also keep soil moist during dry periods. For guidance on designing your system, see:
There are many tips and tricks that gardeners have identified to garden “smarter” through weather extremes – these are just a few. With more gardening or related questions, contact the N.C. Cooperative Extension, Caldwell County Center at 828-757-1290.